The objective of this P01 is to elucidate the biological function(s) of proteins that play important roles in controlling breast development and breast carcinogenesis, through the development and availability of high-throughput protein expression methodologies. In Core A, our immediate goal is to complete and distribute a ready-to-use repository of clones for 1000 full-length cDNAs (fusion and closed reading frames) for genes associated with breast development and breast carcinogenesis. This effort, known as the Breast Cancer 1000 Project (BC1000), exploits recombinational cloning technology that allows DNA fragments to be moved easily from one vector to another. The initial selection of BC1000 genes was primarily determined by the P01 members with the intent of providing the most useful resource to this research community. Monthly meetings with the P01 members continue to provide direction for this project which, in the longer term, will produce a useful resource to the larger community of breast cancer researchers. All resources generated by this project will be accessible to members of the P01 and the broader biomedical research community. The work in this core is divided into two general components: to provide core services and to develop technology for facilitating functional assays using the BC1000 collection. The core services will include the completion and distribution of the BC1000 genes to the members of this grant and the breast cancer research community. These clones will be in a ready-to-use format and the relevant information on these clones will be easily accessible in a public database (Specific Aim 1). To complement these core services, we will develop the technology needed to facilitate functional experimentation using the BC1000. This will include the modification of useful expression vectors and development of automated methods for high-throughput transfer of these clones to these vectors for use in functional or genetic screens (Specific Aim 2). We will also develop and maintain a database to track completed clones and results of experiments done with the BC1000 (Specific Aim 3). This database will provide P01 members a central location to query for available clone information and to stimulate new research ideas from the existing experimental results.